Kitakyushu city, which supported the high economic growth of Japan as a city of steel, was also suffered from serious pollution. Businesses, citizens and administration united to fight against it, which regenerated Dokai bay, once called “The Sea of Death”, and turned the sky with “The Seven-Colored Smoke” to blue. In this process, the city gained the precious resources of environmental technique and tight tie among various sectors, which help the city to take actions against global warming and enlarge the them to Asian area and the world.